Grinding tool



April 17, 1 1 c. K. RAMP ETAL GRINDING TOOL 2 Sheets-Sheet'l Filed Dec. 23, 1948 C. K. RAMP ET AL GRINDING TOOL April 11, 1951 2 Sheets Sheet 2 Filed Dec. 23, 1948 INVENTORS ERNEST F VILTER 7 CHARLES K. RAMP ATT NEYS Patented Apr. 17, 1951 "UNITED STATES PATENT OFFI CE GRINDING TOOL Charles Ramp, Louisville, Ky., and Ernest F.

Vilter, Milwaukee, Wis.

Application December 23, 1948, Serial No. 66,903

inder walls for air brake valves, this is extremely" serious.

It is therefore one of the primary objects of this invention to provide a tool particularly adapted for regrinding the cylinders of air brake valves, in which the body carrying the abrading sheet will be expanded equally in all directions for engaging the work, so that such work will be finished in a true circle.

Another salient object of the invention is to provide a grinding or regrinding tool for cylinders embodying a split annular expanding body having a series of equidistantly spaced slots extending radially from the axis of the body and terminating just short of the outer peripheral edge of said body, so that said body can and will uniformly expand throughout its entire circumference.

A further object of the invention is the provision of a novel formation of slot terminals, so as to not only increase the true flexing of the body, but so that strains at the outer slot ter minals will be distributed over a relatively large area and thereby effectively decrease the likelihood of the body cracking at the slot terminals. I

A further important object of the invention is to provide the body with an inner tapered face and an expander cone for engaging a material part of such face around its entire circumference, so that when the cone is forced into engagement with the tapered face for expanding the body, the body with its radial slots will expand in a true circle.

.A still further object of the invention is to provide a novel and simple means for operating the cone and for rotating the body.

With these and other objects in view, the invention consists in the novel construction, arrangement and formation of parts, as will be hereinafter specifically described and claimed, and illustrated in the accompanying drawings, in which drawings:

2 Claims. (01. 51-4843) Figure 1 is a side elevational view of our novel grinding tool showing the same in place for grinding a cylinder of an air brake triple valve, only the body of the valve being shown and such body being in section.

Figure 2 is an enlarged central sectional view through the grinding tool.

Figure 3 is a horizontal sectional View through the tool taken on the line 33 of Figure 2, looking in the direction of the arrows, the view illustrating the novel radial slots.

Figure 4. is a top plan View of the tool.

Figure 5 is a sectional view through the body 7 of the tool taken on the line 55 of Figure'3,

looking in the direction of the arrows; the view showing the expander cone in operative position in said body.

Referring to the drawings in detail, wherein similar reference characters designate corresponding parts throughout the several views, the letter T generally indicates the novel grinding tool particularly adapted for grinding and truing up internal cylinder walls. In Figure 1, we have shown the tool in operative grinding position for regrinding the cylinder H] of the body i I ofa triple valve l2. In the showing of the triple valve, only the body has been illustrated and all of the other parts have been removed. As this body is a conventional one in construction, the same will not be further described. While we have shown the tool T in use for grinding the cylinder of a triple valve, it is to be understood that the tool can be used for other purposes.

The tool T comprises an annular expanding body I3, preferably formed from spring steel. This body is split at one side, as at 54, so that the body can be expanded when an internal force is applied thereto. The inner face of the body is tapered inwardly and upwardly as at, for a purpose, which will later appear.

In accordance with the invention, the body I3 is provided with a series of equidistantly spaced slots l5. These slots open out through the inner periphery of the annular body and terminate short of the outer periphery of the body. The outer ends of the slots are enlarged as at l6 and these enlargements can be made by boring the body longitudinally at the outer slot terminals. Hence it can be seen that the slot terminals are of a cylindrical shape.

The outer periphery of the body I3 is adapted to receive the abrading sheet l1 and this sheet can be held on the body in any desired way. As illustrated, the outer face of the body I3 on each side of the slit I4 is provided with a substantially semi-circular recess I 8 for receiving the terminals of the abrasive sheet and these recesses receive clamping bars I9. The clamping bars can be removably held in place by screws 26.

Slidably mounted within the body I3 in an expander cone 2! which snugly fits the tapered, inner face [4 of said body. The expander cone is provided with an axial internally threaded bore 22. Means, including the bore 22, is provided for drawing the expander cone 2! inwardly, so as to expand the body l3. This means includes a rotatable shank 23 having a depending threaded extension 24 fitted in the bore 22. The outer end of the shank 23 carries a knurled or like handle 25. If desired, the handle 25 can be provided with radial openings 26 for receiving a hand lever to facilitate the turning of the. shank and.

its screw. The shank is rotatably mounted in a sleeve 21 formed centrally on a bridge strap 2&. Normally, the inner end: of the handle 25 bears against the outer end of the sleeve. The terminals of the bridge strap 28 are slotted, as at 29, and these slots receive the flattened heads 36 of pins 3!, which are rigidly fitted in the body. The outer face of the sleeve 2'! is polygonal in shape, so that a suitable tool or wrench can be applied thereto to permit the rotation of the body 93.

In use of the grinding tool, the abrading sheet I1 is secured to the outer surface of the body and the screw 24 is loosened by turning the handle 25. If the expander cone 2| sticks in the body it is merely necessary to tap on the head or handle 25. The inherent resiliency of the body l3 will now contract the body and the body is placed within'the cylinder to be ground. The; screw 24, is turned in the opposite direction to pull up the cone 2! in engagement with the tapered face 25' of the body and this cone will expand the body and the body with its slots 15 and terminals 6 will expand uniformly in a true circle. The body is expanded sufficiently so as to bring about the desired engagement of the abrasive sheetv H with the cylinder wall. The wrench or other desired tool is now placed on the neck or sleeve 21 and turned, which will rotate the body therewith and the cylinder wall will be effectively ground in. a true circle.

To remove the tool it is merely necessary to again loosen the screw and to give the head thereof a slight tap.

As illustrated in Figure 1 of the drawings, the body of the tool is preferably of a height corresponding to the length of the cylinder 10 so that the entire face of the cylinder will be ground in one operation.

Changes in details may be made without departing from the spirit or the scope of our invention but what we claim as new is:

1. A tool for grinding and polishing internal cylindrical faces comprising an annular body having a longitudinally extending slit opening out through the inner and outer faces of the body, said body also having, a. plurality of equidistantly spaced radially extending slots opening out through the upper and lower faces of the body and the inner periphery of the body, said slots terminating short of the outer periphery of the body, an abrading sheet secured to the outer periphery of the body, and an expander cone. disposed within the body and movable into intimate engagement with the inner surface of said body for uniformly expanding the body.

2. A tool for polishing and grinding internal cylindrical faces comprising an annular body having a longitudinally extending slit opening out through the inner and outer faces of the body, said body also having a plurality of equidistantly spaced radially extending slots, said slots opening out through the upper and lower faces of the body and the inner periphery of the body, said slots terminating short of the outer periphery of the body, the outer ends of said slots being enlarged to distribute strains, an abrading sheet secured to the outer periphery of the body, said bodyhaving its inner periphery tapered in.- wardly toward its upper end, an expander cone. fitted in said body engaging the inner tapered periphery thereof, a bridge detachably connected with said body having a central sleeve, a shank rotatable in saidsleeve having a threaded extension fitted into said cone, whereb upon turn-- ing of the shank, the cone will be drawn in the body to expand the body.

CHARLES K. RAMP. ERNEST F. VILTEZR.

REFERENCES, CITED The following references are of record in. the

\ file of this patent:

UNITED STATES PATENTS- Number Name Date 1,418,721 Larson June 6,v 1922 1,482,089 Moore Jan. 29., 1924 1,604,677 Brandstetter Oct. 26, 1926 2,135,884 Disco Nov. 8, 1938. 2,353,626 Schnaars July: 11, 1944 

